Diffuse microcalcifications only of the thyroid gland seen on ultrasound: clinical implication and diagnostic approach.

BACKGROUND

To evaluate the clinical implications and diagnostic approach of lesions showing only diffuse microcalcifications on thyroid ultrasound (US).

METHODS

From January 2004 to January 2011, a total of 31 patients had lesions showing diffuse microcalcifications alone on thyroid US. Among them, 26 patients (M:F ratio 4:22; mean age 37.5 years, range 15-56 years) who had underwent US-guided fine-needle aspiration biopsy (US-FNAB), subsequent surgery, or follow-up US after 1 year after initial US-FNAB were included. Histopathologic results from surgery or US-FNAB were considered as standard reference. Clinical and US features were compared to standard reference.

RESULTS

Of the disease of 26 patients, 16 (61.5%) were diagnosed as malignancy and 10 (38.5%) as benign. Seventeen (65.4%) of the 26 patients included were diagnosed as having Hashimoto thyroiditis (HT) on a clinical basis. Eight (80.0%) of the 10 benign lesions were diagnosed as benign on initial US-FNAB, and the remaining 2 lesions (20.0%) were nondiagnostic. All malignant lesions were diagnosed as suspicious for papillary thyroid carcinoma (PTC) or PTC by US-FNAB. Of the US features, presence of pathologic lymph nodes were significantly higher in malignant disease compared to benign findings, 10 (62.5%) to 0 (0.0%) (P = 0.003).

CONCLUSIONS

Diffuse microcalcifications only lesions of the thyroid show high prevalence of PTC and lymphocytic thyroiditis. US-FNAB shows an acceptable performance in lesions showing microcalcifications only on thyroid US.